Dental anchorage



May 16, 1933. s MYERSQN 1,909,000

DENTAL ANCHORAGE Filed Nov. 6, 1929 Smou MYERSON I O I, I

g {UNITE STAT S Patented May 16, 1933 PA NT OFFICE,

. SIMON MYERSON, OF BROOKLINE, MASSACHUSETTS DENTAL ANCHORAGE the purpose: of affording an anchorage for adjacent artificial teeth, bridge work, or orthodontic appliances.

' Heretofore and prior to this invention, considerable difficulty has been encountered in the attachment of suitable anchorages'to natural teeth, the anchorages ordinarily constructed for this purpose being incapable of secure attachment without grinding the natural tooth or other F Wise injuring or destroying natural tooth tissue. It is among the principal objects of this invention to provide an anchorage of such construction that it may be slipped over the belly or swell of the tooth crown and be- 2 come securely fixed upon said crown to closely fit the same at the neck thereof, all without necessitating any grinding or other such treatment of the natural tooth.

A further object, of the invention is the provision of an anchorage, the normal shape of which corresponds to the general external contour of a-natural tooth crown, the anchorage being in the general form of an annulus when completed having openable por- A tions in the gingival portion thereof, the construction of the anchorage being such as to wholly eliminate the necessity in many cases and to greatly reduce in all cases the necessity of grinding the natural tooth.

A still further object of the invention is the provision. of a dental anchorage or clasp which is characterized by the provision of .openable wing portions in the gingival por- 9 tion thereof, the proximate edges of said wing portions being provided with means for effecting interlocking V engagement therebetween to securely fix the anchorage or clasp upon the crown with the gingival edge thereof closely embracing the gingival margin of the tooth crown Other objects and advantages of the inven- [tion will'appear more fully hereinafter.

j The invention consists substantially in the ative location of parts, all as will appear more construction, location, arrangement and rel- 6, 1929. Serial No. 405,078.

fully hereinafter, as shown in the accompanying drawing and as finally pointed out in the appended claims, In the accompanyingdrawing, wherein I have shown for purposes of illustration several preferred forms of the invention Figure 1 is a view showing a tooth to which has been attached one form of anchorage embodying the principles of this invention;

' Figure V2 is a perspective view of the an C9 chorage shown in Figure 1;

Figures 3, 4; and 5 are perspectiveviews of modified forms of anchorages embodying the principles of this invention;

Figures 6 and 7 are views showing the application of anchorages embodying the principles of this invention to front teeth;

. Figure 8 is a still further modified form of clasp adapted for use in connection with the tooth shown in Figure l; b

Figure 9 is a'perspective view of a dental clasp of the form shownin Figures 6 and 7 but showing a modified arrangement of interlocking means;

Figure 10 is a plan view ofa substantially flat strip or pattern from which an annulus may be formed to provide an anc age embodying the principles of the present invention; and

Figure 11 is a perspective View showing the flat strip shaped to the form of an anchor age. I

Referring now to the drawing and more particularly to Figures 1, 2 and 7, it will be seen that the invention in one form thereof contemplates the provision of an-anchorage 10 intended for attachment to the crown 11 of a natural tooth, such as the molar or bicuspid or front tooth. It is, of course, well known that the crowns of natural teeth such as that shown in Figures 1 and 7 areYin almost all cases formed with outwardly bulging. walls with the result that it has been a difiicult problem to rigidly secure an anchorage thereon so that it closely fits thetooth irrespective of differences in the horizontal diameters thereof unless resort is had to grinding down the bulge or swell of the tooth crown.

To meet this problem the present anchorage 10 is constructed in the formof an annulus or band or strip of metal, the axial wall 13 of which is contoured to correspond generally to the curvature of the axial surfaces of the tooth crown 11. Inasmuch as the diameter across the gingival edge 1 1 of the band is less than the maximum bucco-lingual diameter of the crown 11, it would be impossible to slip the band over the crown into the position shown in Figure 1 and accordingly the band is provided in the portion adjacent the gingival edge thereof with a pair of openable wing members 15 and 16 which open outwardly to permit the band to he slipped into proper position over the tooth crown.

As appears most clearly inFigure 2 these Wings 15 and 16 are formed by providing a T shaped cut in the buccal or lingual surface,

the vertical free edges 17 of the wings being arranged to meet each other when said wings are brought 1nto closely fitting engagement with the axial surface of the crown. The

vhorizontal edges 18 of the wings preferably overlap the horizontal edge 19 of the T-shaped cut in order to leave no surface of the tooth I crown exposed between opposite edges of the .the tooth crown the wings 15 and 16 are respectively provided with complementally formed interlocking elements. One of these elements is secured to the free edge of the -wing 15 and is inthe forrnof a,T-sliaped or dovetail extension having a stem 20 and a head 21 at one end thereof, the opposite end of the stem being permanently secured, as at .22, to the external surface of the wing 15 in any suitable manner, preferably by soldering,

or. it maybe integral therewith. Secured to the opposite wing 16 of the band or formed integrally therewith is a. block 23 which is provided in the external surface thereof with a T-shaped recess 24 within which is adapted .to be received the T shaped locking element 20-21. It will be observed that when the wings 15.and 16 are brought into close em- .tbrace-with the gin-gival or neck portion of theztooth crown such that the free vertical edges thereof meet and the horizontal edges ,18 thereof overlap the element 202l is received within its seat 24- whereby to securely lock the wings into the position shown in vFigure 1. For aesthetic reasons the band 10 may be cut out, as at 25, in the wall thereof which presents toward the cheek or; lip of the patient. It is important to note,.however, that even though the band is provided with openable wings and-with the cut-out 25 the band is still in the form of a circumferentially complete annulus one-half of which. constitutes the portion immediately above the wings 15 and 16 and the other half of which constitutes the portion immediately below the cut-out 25.

Fi ure 3 shows a modified form of interlock etween the openable wings 15 and 16. In this modified arrangement the wing 15 is provided in the external surface thereof adjacent its free end with a headed, protuberance.

or knob 26. The opposite wing 16 is in turn provided with a leaf 27 one end of which is secured permanently in position, preferably by soldering, as at 28, or formed integrally therewith. Provided in the portion of the 15 and 16 for interlocking engagement between the locking elements thereof each wing may be provided with a gold wire 30 one end of which is secured, as by soldering, to the wing, as at 31. These wires 30 may be twisted together in order to bring the free vertical edges of the wings into abutting relation whereupon the interlocking elements thereof may be brought into operative association for positionally securing the band upon the tooth crown. It will be understood that the wires 30 maybe employed in conjunction with the interlocking means shown in Figure 1 as Well as with any other type of interlocking means, such as are shown in Figure 4: to be now described. \Vhen the interlockin g elements have been brought into engage- :ment with each other the wires 30 may be removed from the band by grinding the same off therefrom- 1 Obviously, other means may be employed in lieu of the wires 30 for the purposespccified.

Referring to this Figure 4 it will be observed that the wing 15 is provided with a locking element 32 the freely projectedend 33 of which is enlarged and provided centrally thereof with an opening 34;. Provided upon the wing 16 or formed integrally there with is a block 35 having a recess 36 of a shape adapted to receive the enlarged head 33 of the interlocking element 32. Provided within the recess 36 is a headed knob or protuberance 37 which is receivable within the opening 34 of the interlocking element 32 when the latter is received within the recess 36. In each of the structures shown, with the exception of that shown inFigure 3, it

will be understood that when the wings 15 and 16 are locked together in the manners described the interlocking devices -Will be substantially flush leaving only the knob 37 to be ground flush by sand paper discs or by other means, either in'the-mouth or before hand so that the externalsurfaces thereof willbe smooth and unobtrusive. The locking members 27 (Figure 3), 32 (Figure 4),

.(Figure 2), etc., are all preferably flush at theirmarginal edges with the'wing surfaces as this a portion of the axial surface of the tooth crown is exposed between edges 18-1 8 and 1901 the band. It'will be understood, of course, that any one, of the forms of interlocking devices hereinbefore referred to may be employed in connection with the structure shown in Figure 5.

Figure 8 shows still another form of clasp or band employing the interlocking means shown in Figure 4', although any one of the other forms of flush-type interlocking means may be employed. In the structure shown in Figure 8 it will be observed that the edge of the band which is adapted to underlie the horizontal edges 18of the wings 15 and 16 is provided with a circumferentially extending shoulder or rabbet 38 whereby to insure a flush joint between said edges 18 of the wings and the portion of the band which they overlap. If desired, a cut-out may be provided in the wall of the band shown in Figure 8 which is similar in all respects to I the cut-out portion of Figure 2. It will be understood, of course, that the openable I wing portions of the band and their associated interlocking elements may be formed in the buccal or lingual walls of the band, although it is preferable, as mentioned above that they be positioned at the buccal side of the tooth crown. It willbe seen that whereas in Figures 3, 5 and 8 the annulus is circumferentially complete in the occlusal portion thereof, this is not so in the case of the structures shown in Figures 2 and 4 wherein the annulus is circumferentially complete in an oblique direction extending fromthe occlusal portion of the band at thewinged side thereof to the gingival portion thereof at the side diametricall opposed to the winged side. The interloc 'inglmeans may be formed as integral parts of t e band or they may be separately secured thereto, as by solderin or the,

like. Furthermore, the band may e provided with a top, as in the case of the usual gold crown, to cover the cusps of the tooth or it may not. For purposes of avoiding all grinding, it is preferable to provide the band without an occlusal surface. Nor is it necessary to provide a cut-out in the buccal wall of the band such as is shown in Figures 2 forced overthe region of greatest diameter and 4.

While the structures hereinbefore described illustrate the use of interlocking means .iii bands orstrips adapted for bicuspid or molar teeth, it will'be seen by reference to Figures 6, 7 and 9 that the same means may be employed for locking aband uponthe front or incisor teeth; Figure 9 illustrates in perspective a form of anchorage for use in connection with an. incisor. In this form of anchorage it will be observed that the lingual wall 39 thereof is intact and that the incisal edge thereof is inturned, as at 40, to overlap to some extent the labial surface of the tooth adjacent the incisal edge thereof. The labial surface of the anchorage is cut-out in such manner as to provide a circumferentially extending portion 41 which is adapted to embrace the gingival portion of the tooth. The circumferential portion 41 of the anchorage is slit in the labial wall thereof, as at 42, to provide a pair of openable wing portions 43 a and 44 which are respectively provided with the interlocking means" designated generally by 45, this means being substantially similar to the interlocking means shown in Figure 3 Figure 6 shows ananchorage which is similar in'every respect to that of Figure 9 with the exception that in place of the interlocking means-shown in the latter figure the interlocking means of Figure 2 are employed. In

both Figures 6 and 9 theinterlocking means are provided in the labial wall of the clasp adjacent the gingival edge thereof. Figure 7 illustrates the use of the interlocking means employed in the structure shown in Figure 4. While Figures 6, 7 and 9 illustrate the em.- ployment of the openable wing portions and their associated interlocking elements in the labial wall of the anchorage, it will be understood that these interlocking wings may be formed in the lingual .wall of the anchorage adjacent the gingival edge thereof and that the horizontal edges 46 thereof may be shaped to overlie the proximatehorizontal edge of the wall of the crown, as in theocase of the structures shown in Figures 2, 3, 4 and 8.

It will be understood thateach of the anchorages hereinbefore describedmay-be attached tov its respective tooth crown without employing any adhesive material. In order, however, to provide for a more permanent attachment it is preferable to employ cement,

' gutta-percha or other such adhesive material in conjunction therewith. In forming an anchorage embodying the principles of this invention the procedure is substantially as follows. An accurate impression is initially taken of the tooth crown upon which the anchorage is to be secured. A hardzmetallic die is then obtained from this impression and an anchorage is selected of a size and shape to fit as nearly as possible this individual die. The

openablewing'portions offthe band .will of necessity open outwardly as the-band .is

of the tooth crown. The wingsflare then drawn into position to snugly; embrace the gingival orneck portionof the tooth crown f:

with the" freeyertical edges thereof preferably abutting each other althoughthey" may 1 The made' to overlap. The interlocking ele- *inent-s are then securedtogether. If theband is too large for its individual die theportion 1 thereof opposite the winged portionsmay be slitto permitthe band to intimately engage the tooth crown throughout the entire extent of the axial surfaces thereof. The band is then placed-in a swedger and swedged to perfectly-fit' the die. -The slit portion, if a slit has been provided,is then soldered. After the slit portions, if any, are permanently g o,- orthobe used independently to'cover an individual tooth.

While in the preceding descriptions the anchorage in its several forms has been described as "being in the form of a circumferentlally'complete annulus, it may, in some instancesybeformed initially in the shape of a substantially flat strip or pattern 46, as

=appearsm'ost clearly in Figure 10. This P strip 46 is provided,preliminarily to shaping it"into annulus formywith thewing element 47 17 and theirassociated interlocking de- Vices 48' in the gingival portion of the strip. i To form the strip into the desired annulus it is merely necessary to bring the edges 4949 1 thereof "into overlapping engagement, as shown in Figure 11, for subsequent soldering -together,'a's'='at 50, thereby providing a circumferentially complete annulus. A strip or pattern suclras'is shown in Figure obviouslyreduces thenumber of sizes that the Inanufactm-er would have to supply in order to meet the' large'variety of shapes and sizes of natural -teeth. For any given natural tooth it is only necessary to modify the strip or pattern lfi to-the style, shape, contour or size} thereof-and then complete the band by I uniting the free edges-4949 together. Itw'ill be understood, of course, that various changes-and modifications may be made in the invention from' time to time without departing from'the principles or real spirit ofthe invention and it is accordingly'intended to claim the invention broadly, aswell as specifically, as indicated in the appended claims.

VVhatis claimed as new and useful is -1. A dental anchorage arranged to encompass the crownof a tooth, said anchorage being in the for mof a circumferentially complete annulus the wall of Which is contoured to the external curvature of the axial surfaces of the too'th crown, a pair of openable wing '-inembers provided in the 'gingival portion of the annulus; the circumferentially extending "edges ofsaid'wingmembers opposite the ginmace-moo gival edges th erebf being formed to overlap the'proxiinate'edge of the annulus, and means for locking said wings snugly about theheck of the tooth.

2. -A dental anchoragearranged to enconipass the crownof a tooth and comprising a circumferentiallycomplete annulus, said annulus beingprovided in thegingival portion thereof with a pair of tongues capable ofbe- 111gfiexedoutwardly as the gingival edges thereof areforced over the crown, and a pair ofwrresrespectrvely secured to each of said tongues 'andadapted to be twisted together whereby to brin g the proximate edges of said tongues 111130 abutting relatlon preliminarily to securing the sametogether. \Vhile'thc anchorage In testimony whereof, I have hereunto af- SIMON MYERSON.

fixed my signature. 

